Hub-operated dynamo for bicycles



-June29, 1943. RABL 2,322,969

HUB-OPERATED DYNAMO FOR BICYCLES Filed Jan. 30, 1940 '7 I ll!!! the dynamo.

iatented June 29, 1943 UNITED HUB-OPERATED DYNAMO FOR BICYCLES Alfred Rabl, Wiener-Neudorf, Germany; vested in the Alien Property Custodian Application January 30, 1940, Serial No. 316,438 In Germany February 10, 1939 1 Claim.

Hub operated dynamos for bicycles are known, in which a roller gear is used to drive the armature and magnetic field of the dynamo in opposite direction of rotation. It is also known in the case of hub operated dynamos to provide a disengaging gear for disconnecting the drive of The known hub operated dynamos require a very large space and are too heavy in weight.

According to the invention, the roller gear runs on a roller hearing. The rolling members of the roller gear are suitably arranged between a member carrying the magnet and a sleeve carrying the armature and running on a roller bearing. The result is a considerable simplification in design permitting of a compact construction, thus it is possible to lessen the dimensions of the dynamo and reduce the cost of production.

The object of invention is shown, by way of example, in the annexed drawing, partly as a sectional View.

The dynamo is housed in the enlarged portion 6 of the hub I. The magnet 9 is secured to member B, whilst the armature I is mounted with its winding 8 on the sleeve II). This sleeve is supported unilaterally by the balls ll of the roller bearing and carries the balls l2 of the roller gear. The balls H run on a bearing ring 3 secured to the stationary axle 2. The balls I2 are held in position by the ball bearingcage I5 provided with a toothed rim [6 with which a pawl l3 may be caused to engage from the handle I! to throw in the gear. The ring I! resting on the balls I! is secured to the cover 5 of the machine.

If by means of the handle H the pawl I3 is caused to engage the teeth l6 of the ball bearing cage I5, the balls 12 are turned round as the huh I rotates, these balls driving the bearing ring I0 and thereby the armature l in opposite direction at an increased speed.

For the collection of current from the revolving armature a slip ring I8 is fastened to the armature and insulated, this slip ring being electrically connected with the end I9 of winding 8. A contact disc 20 is: forced against the slip ring I8 by a spring 2| encircling the stationary axle 2 and being passed through a recess 22 of the axle. The end 23 of the spring is connected with the terminal screw 24 from which the current is taken. Spring 2| and slip ring 20 are so arranged as not to get into contact with the stationary axle and sleeve.

I claim:

A gear drive for dynamos carried by bicycles of the type including a wheel hub, comprising a sleeve carrying a dynamo element, a ball bearing between the sleeve and hub, 'a-ball gear for driving the sleeve, said ball gear including a ballcarrying cage having an externally-toothed extension surrounding the hub, and manually-oper- :able means to cooperate with the teeth of the extension to selectively fix or free the ball gear relative to the hub, the balls of the bearing and the balls of the ball gear being in a vertical plane transverse the wheel hub.

ALFRED RABL. 

